I just downloaded PhProxy from here. When I went to some IP locator site my IP was a Dallas/Texas IP. Is there any way to change the IP PhProxy uses? I couldn't find a way to do it.
PHProxy - like all proxies - accepts requests from any of a number of IPs and acts on their behalf to fulfill that request. The IP you're seeing is almost certainly the IP address of your webserver, and no you can't edit some setting to change it. Your server makes a request to some address and includes its own address - this is how the remote end knows how to answer back. You couldn't change this with a PHProxy setting even if you wanted to - if you could, your packets wouldn't get back to you.
You could get a different webhost, if a Dallas-located IP is a real problem, but it would be locked to the new webhost just the same. Webservers can't exactly IP-hop...
Related
I plan to make a web application. The workflow will be the client scan QR code using his phone to go to some specific URL.
But interested to me is there any option to I can limit visit that URL if the request didn't comment from a specific WiFi network? I do not want to anybody take a photo and fake requests.
There are multiple ways to do it:
If your specific WiFi network has a fixed WAN IP / IP range, you can write your application to detect the client IP and check if they came from there. You may check $_SERVER['REMOTE_ADDR'] for the client's IP (if your server is not behind reverse proxy). Your server is still publicly available, but your PHP code will only allow the whitelisted IP to access the certain URL path.
If you want even better security, you may place your server in your local network. You can use local IP in your QR code for users to access it. This way, the server will not be available on the internet at all.
I have website and have one page for receiving some news (newly registered users, activity, etc.) and is restricted for everyone except for my IP (Page for only me to view).
I'm interested if there is a way that someone else can "fake" my IP and view this file?
P.S. I am aware of other ways of doing this.
Usually, you dont get fixed IPs, most provider give dynamic IPs. So if you restart your Router, your IP will change and make it impossible to access the page again. If you get a fixed IP, it should work. He can ofc. modify the IP, but then he wont get the response back.
Converting my comments to an answer.
It depends on how you are trying to get the client's IP address. If you are:
only using $_SERVER['REMOTE_ADDR'] to get the ip address
don't have a shared ip address
don't use a (shared) proxy
You should be just fine, because a possible attacker can technically spoof the ip address, but that would not work because, (as Andrey) rightfully pointed out to me the tcp handshake would simply fail.
Some caveats:
Your IP may change at some point effectively locking yourself out.
When you are behind a proxy / internal -> external router / vpn / otherwise shared ip other people in the same network might also have access
Never ever ever use $_SERVER['HTTP_X_FORWARDED_FOR '] because this can be spoofed easily.
I'm a user of a certain forum, but recently my IP adress has been being blocked.That's not my fault but some users probalbly broke the rule and his ISP or IP address is same or close to mine, so I was enmeshed.
I rent a web server, so now I try to post comments to the forum from my server, but it fails.
When I post a comment using a form in the site, the error says that the referer was wrong.
I tried header() function using PHP but it doesn't work.
I tries to change referer but still it doesn't work.
I think if I could have a client in my web server, the IP and host change in posting comments, without changing referer information.But I don't know how to do this.
The restriction is temporary, maybe a few weeks, so I don't necessarily need a perfect and permanent solution.
Is there any ways to solve this problem?
If they're blocking you based on IP address, then it's the web IP address of your local network that they're blocking. If they've decided to block a range of IPs then you have a larger problem depending on your host.
A few things you can try:
Chances are (unless this is a work account) that you're using a dynamic ip address from your host. A lot of work accounts use a dynamic IP too, but you would need access to the modem (since you're probably not the corporate network administrator). Sometimes to get a new IP address from a completely different range by unplugging your cable or DSL modem and plugging it back in after about 30 seconds. Most electronics clear instantaneously (unless they have an onboard battery backup), but in the case of network components they purposely build in a few seconds of wait time in DHCP servers before providing a completely different IP address. Usually when I'm having a problem on my local network or doing an upgrade and unplug my modem after about 10 minutes of work when I plug my modem back in I have a new IP so I have to go through all of the trouble of re-whitelisting myself everywhere (so I know this works).
You could try connecting to the boards through your cell phone if you can tether your cell phone to your workstation or desktop. This will provide you with an IP address through the cell phone carrier's network (Note: it might violate the TOS).
You could do as #Bergi suggested and use a proxy. Some web browsers (like Opera) allow you to specify a proxy in the browser without forcing all of your desktop traffic to a different network. You can obtain a proxy server address from several resources, but this is one of my favorites. Be sure to use an HTTPS proxy in order to have the best defense against someone packet filtering and catching your credentials. People can still capture the initial handshake for SSL and decrypt your communications (so make sure this is what you want to do.)
You can try to force inject headers into the message board and make your server post for you. Good forum software will check the referrer and the user_agent to see if you are a "real person" (however real the programmer felt you needed to prove). If there is a CAPTCHA you will need to be able to see the image, hear the sound, or use a plug-in to break it. (This will require research). Chances are your web server is using a static IP, so there is nothing to prevent the board from blocking this one as well. (You will not be able to change it.) If the web host has strict guidelines about using their servers for this sort of thing it might *cost you your account*. I will not provide an example for this on this board. But you can check out a book called WebBots, Spiders, and Screen Scrapers.
How to change ip address such that it does not reveal our original address when using $_SERVER['REMOTE_ADDR']; in php
You need to use a proxy server if you're trying to access a website from a different IP than your own. Wikipedia has more information.
There are several options I have in mind for this. I will go from the simpler to the more complicated one.
First, you could use a proxy server and ask him through an HTTP request made by your program or your browser, to fetch a resource for you. The proxy server will take the role of querying a resource in your place to the target service.
Example :
You want to retrieve the main page of the domain stackoverflow.com. You ask the proxy server to ask stackoverflow's HTTP server to send him the main page and he will forward it back to you.
To SO webserver, the superglobal $_SERVER['REMOTE_ADDR'] variable will correspond to the proxy server's IP address and not yours. However, the HTTP protocol implements some fields such as HTTP_VIA, HTTP_X_FORWARDED_FOR, or HTTP_FORWARDED which can be used to know if the current HTTP request is made by a proxy or not.
A transparent proxy will not specify those fields and will not modify your request whereas a non-transparent proxy may reveal the original IP address of the original requester. You got to use a reliable proxy which will act as you intends it to act. Another thing to consider is the use of an SSL tunnel between you and the proxy to avoid eavesdropping.
The second solution is to use a VPN (Virtual private network) server. It would be too complicated to fully explains how this works, but remember this, when you are connected to a computer using a VPN service (like l2tpd, pptpd ...) it's like you were on the same LAN with this computer. So you can transparently make requests to a webserver and he will never find out what's your real IP address.
A third solution could be to use linked nodes based network such as TOR. It's a free network you can connect to, and you will be completely anonymous to regular people. The TOR network power is to provide a network of many nodes and each nodes doesn't know anything about other nodes, so even people connected to the TOR network cannot know anything about you. I suggest you to read more about this if you're interested.
There are more complicated other solutions such as TCP session hijacking which is generally used to fake IP addresses and literally steal another computer's TCP connection, but this is out of the scope of this answer.
Is it possible to fake or hijack a content of $_SERVER['REMOTE_ADDR'] variable?
I would like to fake a request with:
$_SERVER['REMOTE_ADDR']='127.0.0.1';
How could I do that with PHP? Can CURL do that somehow?
I assume that you mean faking it remotely. The short answer is yes you can. The long answer about how easy it is depends on how you want to fake it.
If you don't care about receiving a response, it's as trivial as opening a raw socket to the destination and forging the source IP address. I'm not sure if it's really easy to do in PHP since all of PHP's socket implementations are at or above the TCP level. But I'm sure it's possible. Now, since you're not in control of the network, the response will not go back to you. So that means that you cannot (reliably anyway) create a TCP connection via a trivial forged TCP header (since the syn-ack does prevent this by requiring two-way communication).
However, if you can compromise the gateway the IP is off of, you can do whatever you'd like. So if you compromise the wifi router a computer is connected to, you can pretend to be that computer, and the server won't tell the difference. If you compromise the ISP's outbound router, you can (in theory at least) pretend to be the computer and the server won't tell the difference.
For some more info, see these following links:
ServerFault Question
Symantec Article
Linux Security Article
However, you will only be able to forge the 127.0.0.1 loopback address under TCP if you actually compromise the local machine/server. And at that point does it really matter?
Important
If you're using a framework to access this information, be absolutely sure that it does not check the X-HTTP-FORWARDED-FOR header! Otherwise it's trivial to fake the IP address. For example, if you're using Zend Framework's Zend_Controller_Request_Http::getClientIp method, be absolutely sure that you pass false as the parameter! Otherwise someone just needs to send an HTTP header: X-Http-Forwarded-For: 127.0.0.1 and they now appear to be local! This is one case where using a framework without understanding how it works in the backend can really be bad...
Edit: Relevant
I wrote a blog post recently about how I stumbled across a vulnerability in StackOverflow's application. It's very relevant here, since it exploits a very similar mechanism to what this question is looking for (although the circumstances around it are somewhat narrow):
How I Hacked StackOverflow
The remote address is not something added out of courtesy, it's used in the IP protocol to route packages, so if you send a package with a fake address, you will not receive a response, and since you're talking about a HTTP request, which is delivered over a TCP connection, which takes several IP packets (and the matching responses) to set up:
No, that's impossible (except of course by actually sending the request from the same host via the loopback interface).
Apache populates $_SERVER['REMOTE_ADDR'] from a TCP socket that it uses to communicate with your browser. It is IMPOSSIBLE to influence this variable over the open internet because of the three-way-handshake. If the client and the server is on a broadcast network, like wifi, then you can sniff the wire and complete the handshake.
If you browse via a proxy, $_SERVER['REMOTE_ADDR'] may be set to the proxy's IP address rather than the end user's.
There are other headers which you can use instead in this case: This page gives a function which checks all the possibilities and provides the address most likely to be the end user's:
http://roshanbh.com.np/2007/12/getting-real-ip-address-in-php.html
However if the user is proxying using a badly configured proxy, or a malicious one, or one designed to anonymise the end user, then you won't be able to guarantee any of the headers other than REMOTE_ADDR (which would only lead you as far as the proxy).
If your end user is browsing via HTTPS, then REMOTE_ADDR will always be his IP address; you can't use proxy forwarding via HTTPS. Therefore, the one way to be absolutely sure of his address is to get him to open your site in HTTPS.
You can overwrite any item in the $_SERVER array, including the one you mention, in your server; of course, not in someone else's.
However, it won't change your computer's IP address.
REMOTE_ADDR
The IP address from which the user is viewing the current page.
You can request script using proxy, etc. to change IP address but you cannot set there any text you want.
That is a variable set by apache or whatever server you're using. You cannot spoof it.
You may run $_SERVER['REMOTE_ADDR']='127.0.0.1'; at the beginning of the scripts, but i doubt thats what you're trying to do